Jimthompsonite

Formula:  (Mg,Fe)₅Si₆O₁₆(OH)₂

Origin of name:  For James Thompson, American petrologist

Crystal system:  Orthorhombic

Crystal class:  2/m 2/m 2/m

Twinning: 

Unit cell: 

Colour:  Colourless to light pinkish brown

Diaphaneity: 

Luster: 

Habit:  Crystals prismatic, in radiating groups; intergrowths in anthophyllite and cummingtonite

Hardness: 

Specific gravity:  3.03

Cleavage:  1; {210}

Tenacity: 

Streak: 

Synonyms/varieties:

Comments:  Dimorphous with clinojimthompsonite